This relates to a device to hurl baseballs or the like to a player during practice ball-hitting sessions.
It is known that skilled baseball pitchers normally put a controlled spin on almost every ball thrown, causing the ball to curve away from an otherwise normal trajectory, curving either up, down, or to either side, depending upon the direction of the spin. Skilled tennis players likewise hit the ball to make it spin and curve. Curve-balls are more difficult to hit in contests such as baseball games and tennis matches.
For baseball batting practice sessions there are electric-powered ball-throwing machines available which can be adjusted to throw curve balls at various set speeds, but these are relatively expensive and heavy to transport to a field for non-professional team practice, and electric power is generally not available at the pitcher's mound at most amateur practice sites. Electric-powered devices to hurl tennis balls are likewise available, but expensive and heavy.
Elastic-powered slingshots and catapults are well known, but none are known which provide multi-directional spin control. U.S. Pat. No. 5,123,643 describes a slingshot system capable of putting a spin on a baseball, but it is limited to a down-spin exclusively. U.S. Pat. No. 4,261,319 describes a slingshot for spinning a non-standard football out from a guide rod centered through the length of the ball, but this is clearly not applicable for baseballs, tennis balls, and the like.
It is the object of this invention to provide an easily portable, light-weight, non-electrical and relatively inexpensive device that has the ability to throw a baseball, tennis ball or the like with a controlled spin in any chosen spin direction, and with various settings for a controlled maximum forward velocity.